This application for a Specialized Center of Interdisciplinary Research (SCOR), aims at identification of female osteoporosis risk genes using the genomic convergence approach. It will integrate efforts of the Orthopedic Research Program and Genetics Core (Dr. Deng), and the Bone Biology Program (Dr. Lynda Bonewald), at UMKC, and the Osteoporosis Research Center (ORC) at Creighton University (Dr. Recker). The ORC is 2.5 hr drive from UMKC. The Clinical Core, located in the ORC at Creighton is described herein. The overall objective Core is to recruit 160 human subjects during four years to support work in Projects 2 and 3. Steps in recruitment are: search the ORC archive; make telephone contact; schedule candidates who pass the telephone screen; if eligible, complete clinical examination and collect specimens. Steps in specimen collection are: perform phlebotomy to obtain 130 ml of peripheral blood; schedule for bone marrow aspiration; perform 10 ml bone marrow aspiration; transport the specimens immediately to the laboratory Dr. Lundberg (co-l of Project 2) for cell isolation at Boys Town National Research Hospital (contiguous with Creighton University Medical Center, where the ORC is located). The Creighton ORC has a long history of successful recruitment to clinical research studies. We will recruit 40 subjects during each of the Years 1-4. The cohort will include 80 healthy Caucasian female subjects at age 50-55, half with high, and half with low BMD at the spine or hip (top or bottom 20% in agematched population). Each group will be half pre- and half post-menopausal. We will also recruit 80 agematched healthy males with high or low BMD (top or bottom 20%). 80 age matched Caucasian males with discordant BMD values (40 with high and 40 with low BMD values) will also be recruited. Case and control subjects (e.g., those with high or low BMD) will be closely matched for age. The subjects will be recruited from our archive of ~28,000 persons who have all signed consent to allow us to contact them for future research opportunities. This large database will be used to locate candidates for recruitment into this study.